Today's Launch Of Titan Rocket Has Nasa Edgy

CAPE CANAVERAL - — America's newest and biggest unmanned rocket, the Titan IV-B, is scheduled to launch today, but there is more at stake than the $250,000 Defense Department satellite it is carrying.

The launch, scheduled for between 12:36 p.m. and 4:36 p.m., is more than an unveiling of the Air Force's latest and strongest heavy-lift rocket. It's the precursor to a major battle over a scientific launch.

"This is a qualifier for Cassini [Saturn probe)," said Vic Whitehead, Lockheed Martin Astronautics vice president for Titan. The company makes the rocket.

Cassini, the last of NASA's massive space probes, is the reason this unassuming launch is gaining so much attention and why NASA officials are privately nervous. The fuel source for the probe, which is to study Saturn and its rings, is 72 pounds of radioactive plutonium.

Cassini is to fly on the Titan IV-B's second launch, scheduled for Oct. 6. The probe cost NASA $1.4 billion to design, and the Europeans are paying an additional $400 million. NASA also is paying $450 million to launch Cassini.

If something goes wrong with today's launch, the Cassini mission could be delayed. If Cassini isn't launched by Jan. 4, 1998, the $1.8 billion probe will have to wait until at least 1998.

NASA officials are antsy because new rockets have a high "infant mortality rate," said John Pike, space policy director for the American Federation of Scientists, a Washington think tank.

In the past two years, there have been several first-launch rocket disasters. The European Ariane V (the closest heavy-lift rocket to the Titan), the Lockheed Martin Launch Vehicle, the Conestoga and the Pegasus XL all failed spectacularly on their first launches. Ariane V blew up despite a long line of successes in earlier versions.

"The first [launch) is kind of tough," said Air Force Lt. Col. Ev Thomas, Titan launch squadron commander. "You don't want to make any mistakes."

The solid-rocket motors on the new Titan have been test-fired five times. Lockheed Martin double-checked its rocket motors after last month's Delta rocket explosion because the same company builds both motors.

The new Titan, named IV-B to distinguish it from the old IV-A, has bigger twin strap-on solid rocket motors that increase its lift capacity by 25 percent. The rocket also has a new guidance system. And instead of custom-making the core of the rocket for every launch, Lockheed Martin has designed a cheaper, more standard core.

None of the rocket's improvements are any comfort to anti-nuclear groups, who say it is too dangerous to launch radioactive material, even on a well-tested rocket. The Delta that exploded, for example, is the nation's most reliable rocket.